Improvement in machines for cutting screws on bedstead-rails



UNITED VSTATES PATENT Fries.

Il. GROSS AND lVM. CAMPBELL, OF TIFFIN, OHIO.

IMPROVEMENT IN MACHINES FOR CUTTING SCREWS ON BEDSTEAD-RAILS.

Specication forming part of Letters Patent No. 8,019, dated April 1, 1351.

T0 all wtont t 711/663/ concern:

Be it known that we, II. GRoss and TV. CAMPBELL, of Tiffin city, in the county of Seneca and State of Ohio, have invented eertain Improvements in Apparatus for Cutting Screws in Bedsteads; and we do hereby declare that the following is a full, clear, and exact description of the principle or character which distinguishes them from all other things before known,and of the usual manner of inaking, modifying, and using the same, reference being had to the accompanying drawings, of which- Figure l is aperspective View ol' the whole apperatus forcuttin g screws on the rails; Fig. 2, a View of the cylindrical cutter stock or socket; Fig. 3, a section of the same; Fig. 5, detached Views of the V-cutter; Fig. 6,a View of the apparatus for holding and cutting the screw in the post, and Fig. a a section of the post-screw cutter.

In manufacturing bedsteads the great difficulty has been to form the joints between the posts and rails so tight that vermin cannot enter and reside in them. For this purpose in bedsteads put together by right-andle'ft-hand screws on the ends of the rails, (which is found to be the simplest and cheapest way in which bedsteads can be constructed,) it is absolutely necessary that the screws both on the rail and in the posts shall begin and end at the same part of a turn, and it is also neeessary that the screws should it with great exactness. The machinery Vfor these purposes, though constructed in great variety, has hitherto been able to perform its work with only an approximation to perfection.

The design of our invention is to accomplish these purposes in a perfect manner and at the same. time be rapid and simple in its operation.

The invention consists, principally, in the Inode of securing the V-cuttcr toits socket and enabling it to withstand the strain without springing ol'f lfrom its work.

In the drawings, a is the bed or frame similar to the bed of an ordinary lathe. One of the head-blocks I) is lixed stationary to the bed and the other b is made to slide to and fro to accommodate different lengths of rails, and is secured in its position by the set-screw c, which passes through a slot in the front of the bed a. The other parts of the two headblocks are similar, except that one is adapted to cut a right and the'other a left handed screw and will be described under the same letters.

d is an arched standard,through the top of which a screw c passes. Below this screw is a hollow sunk in the head-block, which has a vertical mortise in it at this place,in which is inserted a piece f, which is more or less elevated by, a wedge g, inserted in a mortise in the head-block under the piece f and is kept from slipping back by a set-screw 7L. The screw c and the pieeef are for adjusting the position of the tenon and holding itfirm while the screw is cutting, the shoulder of therailtenon being set up against a shoulder on the head-bloek,\vliich insures the screw eo1n1nencing at the right point.

On the back end of the head-block is a standard tj, through which the screw 7e (having the same pitch of thread as the screw required to be cut) runs. On the end of this screw is a socket or cylindrical head l, which is large enough to contain the tenon. Near the end of it is the V-cutter m. (See Figs. 2, 3, and 5.)

yn is a recess made in the circumference of the cutter-head near the end thereof to receive the V-cutter, the widest portion of said recess extending'through to the interior of the head. The sides of the recess are shaped to correspond with the sides of the V-cutter which is fitted to them. The narrow portion of the recess into which the shank of the V- cutter is fitted does not extend entirely through the cylinder. It contains a female screw p, into which is screwed a male screw q, after being passed through the shank of the V-cutter which lies in this part of the recess. The V-cutter is made of the best cast-steel in the forni represented in Figs. 3 and 5, and is set in the aforesaid recess or seat in the manner represen ted in Fig. 3, having' the two outer points of the cutting end of the V-cutter, which are slightly beveled, resting against the interior surface of the cylindrical head,where it is beveled or sloped outwardly next the wide end ot' the recess, and the butt-end of the V-cutter resting against the cylinder at n, and the tapered end of the shank let into a notch in the cylinder at the small end of the recess at n2, so that as the resistance increases during` the operation of cutting the hold of the V-cutter upon the head or socket Z also increases, and when the cutter is properly adjusted and the screw q inserted it is almost impossible for the cutter to leave its seat, however hard the wood may be upon which it is to operate, and yet when it is required to disengage it from the head for sharpening or for any purpose it can be done screw is then Cut by turning the handle 0i the screw t, which has a cutter on its end which enters the hole in the post and cuts the female screw, always commencing` at exactly the same point in each p0st,which, in connection with the before-described apparatus for cutting the male screws, insures a perfectly tight-'litting joint and also causes the right and left hand screws on the two ends of the rail to come up to a close joint at the same time.

Having thus fully described our improvements in cutting screws, what we claim as new therein7 and which we desire to secure by Letters Patent, is-

The peculiar form and manner of securing the V-cutter to the cylindrical head, as described-that is to say, making the cutter as represented and letting the tapered end of the shank into the recess,bringing the angular shoulder against the cylinder and sustaining the beveled points against the interior beveled surface of the cylinder-head, by which arrangement the instrument during lthe operation oi cutting is forced firmly against the head, the strain upon the confining-screw being thereby greatly reduced and the cuttingtool itself strengthened.

1I. GROSS. W. CAMPBELL.

Witnesses:

URIAH GREEGER, G. I. KEEN. 

